Joint for concrete structures



June 15, 1943. A. TATE ,321,

JOINT FOR coucnnm' swnucwunms Filed July 15, 1941 2 Sheets-Sheet 1 Wain-Jail June 15, 1943. A. TATE JOINT FOR CONCRETE STRUCTURES 2 Sheets-Sheet 2 Filed July 15, 1941 /6 /7 I'll mm v mqg Patented llune 1943 'Alexander T'ate, Fareham, England Application July 15,1941, Serial No. 402,521 In Great Britain March 1, 1941 3 Claims.

This invention relates to joints for concrete structures, and has for its principal object to provide improved jointing means for preventing leakage of moisture between contacting surfaces of adjacent structural slabs or blocks of concrete, imitation stone, or other plastic material capable of setting to a hard mass and which may contain sand or coarse or fine aggregate, all deemed to be included herein in the term "concrete.

It is another object of the invention to provide improved means for waterproofing such joints whilst also allowing for the contraction of the slabs or blocks of concrete on setting to the hard condition and any further alteration due to temperature changes. The word "waterproofing is to be understood to include proofing against liquids other than water.

-I-Iitherto it has been the practice to embed a metal jointing strip in the concrete of the adjacent slabs or blocks during construction, this strip extending, where practicable, for the full length of the joint, and usually having a ripple or corrugation to allow for shrinkage of the slabs on setting or expansion or contraction thereof due to temperature or other changes.

This type of joint seal, however, has the disadvantage that, unlessspecial precautions are taken, the contraction of the concrete on setting may loosen the jointing strip and so destroy the waterproofing quality of the seal. Moreover, in the'event of damage to or failure of the seal, considerable difficulty and labour are involved in its replacement. It is also to be noted that as a joint seal of such type requires the metal joint ing strip to be embedded during formation of the concrete slabs or blocks the strip is exposed to risk of damage by workmen engaged in the pouring of the concrete and in the dismantling or erection of shuttering or formwork used for outlining or forming the adjacent slabs or blocks. Furthermore, such a seal cannot be employed when precast concrete slabs are used for the structure.

An important object of the present invention is to overcome these difliculties and to provide an improved waterproof seal for joints in concrete structures which is of very highly reliable character and construction.

A more specific object is to provide for sealing a joint between two concrete slabs or blocks, a channel formed partly 'in one slab or block and partly in the other and extending lengthwise of the joint, slots extending in each slab or block from said channel, bolts placed in said slots,

' following description of suitable forms ofwater--- strips of sealing material placed about said bolts along the side walls of said channel, a jointing strip disposed in said channel and having lateral edges engaged over said bolts and with said sealing strips, and clamping bars secured by the bolts against said lateral edges.

Yet another more specific object is to provide, for sealing a joint between two concrete slabs or blocks, a channel formed partly in one slab or block and partly in the other and extending lengthwise of the joint, slots extending in each slab or block from said channel, a first series of bolts placed in said slots, a second series of bolts secured in the slabs or blocks adjacent said chan nel and with their axes at right angles to those of the first series of bolts, strips of sealing material placed about the bolts of each of said series, a jointing strip extending longitudinally of said channel and engaged adjacent its lateral edges over both said series of bolts, and with said sealing strips, and clamping bars secured by said series of bolts against said lateral edges.

Yet other objects will be understood from the proof joint seals according to the invention and which, given purely byway of example, are

shown in the accompanying drawings, wherein:

Fig. 1 depicts part of a concrete structure embodying concrete slabs or blocks and having applied to the joint between the slabs or blocks a joint seal in accordance with the present im-' provements.

Fig. 2 is a transverse section taken on the line Ill-II of Fig. 1;

Fig. 3 is a section on the line III-III of Fig. 1;

Fig. 4 is a half-view taken similarly to Fig. 2, and showing a second form of seal; and

Fig. 5 is a view similar to Fig. 4 showing a modified form of seal;

In Figures 1 to 3, which may be regarded as i1- lustrating the waterproofing of the joint between slabs or blocks of a concrete structure such as a wall or floor. The joint seal is applied at a re' cess or channel I formed in the surface of adjacent slabs or blocks 2, 3 and extending lengthwhichare formed in the slabs to accommodate the heads 1 of a seriesof bolts 8 whose shanks are laid in the slots with a large rectangular washer 9 mounted beneath each bolt head 1 2,321,873 6 (of greater width and depth than the slots) desired after removal of the shuttering or formwork used in casting the slabs. On each side of the channel, a strip if! of resilient or compressible sealing material, for example rubber, is mounted about the threaded ends of the bolts 8. Also a jointing strip ll of metal or other suitable material and having a central longitudinal ripple or corrugation l2 formed therein is laid along the floor of the channel I outside of the joint 4 and has its marginal edges bent at right angles to lie close to the side walls of the channel. By means of holes previously drilled therein, the strip H is engaged by the threaded ends of the bolts 8, and a rigid compression bar i3 of metal or other suitable material, also ready drilled for the purpose, is placed over the bolts to press upon the jointing strip I I. A nut I4 is then threaded onto each bolt, with or without the interposition of a locking or other washer l5, and drawn up tightly to clamp the jointing strip ii firmly between the compression bar I3 and the strip of sealing material 40. the latter being also forced into intimate sealing'contact with the side walls of the channel i. In this way the joint 4 is completely sealed against leakage from the inside or the outside of the structure and contraction and/0r settling of the adjacent slabs 2, 3 on hardening is accommodated by the ripple ii? in the jointing strip H. Finally, the recesses 6 accommodating the bolt heads I, and the slots 5 in which lie the bolt shanks, are lled with cement mortar or the like.

In the second form of seal illustrated by Fig. 4, the marginal edges of the jointing strip i l are extended, as at Ila, to lap over the outer edge of each channel side wall for a sufiicient distance to permit of a second strip IQ of sealing material to be inserted beneath each'jointing-strip part Ila, and a second compression bar ll, mounted on bolts N3 of a second series which are embedded in each slab 2, 3 is clamped down on each slab by nuts l9 threaded onto the embedded bolts after the slots 5 and recesses 6 have been filled as aforesaid and the mortar has set therein; These bolts it are preferably located mid way between adjacent bolts 8. In this way, two water-tight seals are formed in planes at right angles to each other, and are arranged in series with respect to the path of leakage of moisture through the joint 4 between the slabs 2, 3.

The joint seal shown in Figure 5 comprises a modified form of compression bar comprising a length of angle iron 253. Such. a bar has greater rigidity, and enables fewer bolts to be used.

Joint sealing and waterproofing means according to the invention may be employed with particular advantage, in reservoirs and tunnels. In the latter application, the channels I in constructions such as are shown in Figs. 1-4, would generally be on the inside of the tunnel and could be used as conduits to carry lighting cables or other services. Where the channels are used in reservoirs they may accommodate any piping or such other form of service apparatus as may be required. Any of the forms of joint seal described or illustrated may be used for sealing joints in walls, floors, roofs and arches- It will further be understood that the composition or character of the jointing strips and the compression bars will be selected according to the conditions of service to be encountered. Normally, the metallic parts will be of steel coated with paint where exposed to the water or liquids or to the atmosphere, but, if desired, copper or brass, other alloys, or plated or anodised parts may be used. It will be noted, however, that in each. costruction' the ripples or corrugations extend in a direction away from the concrete and that the strip H is completely outside of the joint and thus unaifected by movements in the:

joint.

Obviously, there may be more than one of such ripples or corrugations in the strips H, such as tworunning parallel to each other one on each sideof the longitudinal centre line of the strips;

What I claim is:

1. For sealing a joint between two'concrete slabs or blocks, a channel formed partly in one slab or block and partly in the other and extending lengthwise of the joint, slots extending in each slab or block from said channel, bolts placed insaid slots, strips of sealing material placed about said bolts-along the side walls of said channel, a jointing strip disposed in said channel and having lateral edges engaged over said bolts and with said sealing strips, and clamping bars secured by the bolts against said lateral edges.

2. For sealing a joint between two, concrete slabs or blocks, a channel formed partly in one slab or block and partly in'the other and extend-- series of bolts placed in said slots, a second seriesof bolts secured in the slabs or blocks'adjacent' said channel? and with their axes at rightangles to those of the first series of bolts, strips of sealing material placed about the bolts of. each of said series, a jointing strip extending longitu' dinally of said channel and engaged adjacent its lateral edges over both said series ofbolts, and with said sealing strips, and clamping bars se-- cured by said series of bolts against said lateral edges.

3. For sealing a joint between two concrete slabs or blocks, a channel formed partly in one slab or block and partly in the'other and eXtend-- ing lengthwise of the joint, slots extending in each slab or block from said channel, bolts placed in said slots, strips of sealing material placed 

